Greubel Forsey’s striking Grande Sonnerie

The watchmaking marque presents its first Grande Sonnerie – considered to be one of the greatest of watchmaking complications

The Grande Sonnerie represents a culmination of eleven years of research and development, the filing of two patents, and the assembly of no fewer than 935 parts for Haute Horlogerie brand Greubel Forsey.

Since the very beginning of their partnership, Robert Greubel and Stephen Forsey have been thinking out what their own, resolutely contemporary interpretation of this regal complication could be. For eleven years, the Grande Sonnerie shaped their day-to-day lives, during which they worked to assemble the 935 parts of this timepiece, striving to achieve absolute harmony between the movement, the exterior, and the acoustics.

This timepiece represents the quintessence of their expertise and their ideal of watchmaking excellence. This Grande Sonnerie has powerful acoustics. It is water resistant to 3 ATM. It is ergonomically designed for optimum ease of use, while an exceptional repeater power reserve enables it to run for about twenty hours in “Grande Sonnerie” mode.

The timepiece is equipped with a silent striking regulator and a Tourbillon 24 Secondes, all housed within the standard dimensions of a Greubel Forsey case. The most important elements and indications (such as the tourbillon, the cathedral gongs, the striking hammers, and the power reserve and mode indicators) were incorporated with the greatest care to ensure architectural balance. The watch designers succeeded in housing the 935 parts comprising this timepiece and its exterior in a space measuring 43.5 MM in diameter and 16.13 MM high.

The Grande Sonnerie, which is Greubel Forsey’s most complex creation to date, houses a movement that is manually wound.  But the striking mechanism features a self-winding system that provides about 20 hours of power reserve in Grande Sonnerie mode.

The minute repeater and its additional striking mechanism sounds the exact time on demand, down to the minute. The specific characteristics of this timepiece include 21,600 vibrations/hour and a 72-hour chronometric power reserve.

The latest offering from Greubel Forsey comes in three modes: the Grande Sonnerie (which strikes the hours and the quarters in passing), Petite Sonnerie (which strikes the full hours in passing) and Silence (which does not strike in passing). The pure and rich sound of the Grande Sonnerie is enhanced by an acoustic resonance cage made from titanium.

Greubel Forsey, which is now part of the very exclusive circle of the few watchmakers offering a Grande Sonnerie, will offer only five to eight pieces of this timepiece in a year.